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A comment on The evolution of a structural code editor.

Re:The evolution of a structural code editor by herrington_d on Monday January 06, 2025 @01:15PM (#42613356)
> Better type information. Because the program is always in a valid state the type checker can always run and give meaningful feedback.

Note that programs can be syntactically well-formed but ill-typed. For example `let x = true + 1` has valid syntax but produces an "undefined" type for the variable `x`, if the type system does not support type error recovery.

A quote from the great paper from POPL 2024, https://hazel.org/papers/marking-popl24.pdf

> If a type error appears _anywhere_, the program is formally meaningless _everywhere_

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Re:The evolution of a structural code editor by crowdhailer on Monday January 06, 2025 @01:33PM (#42613611)
The EYG type system does support recovery, so you will get multiple type errors if that's the case in the program.
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Re:The evolution of a structural code editor by herrington_d on Monday January 06, 2025 @05:55PM (#42617023)
My point is that type error recovery is the property of the type system. Not the property of structural code editor.
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